DESCRIPTION: The core facility of the program project funded a Bruker IFS 66 Step-Scan FTIR instrument. The FTIR instrument is housed in Room 501 of the Goddard Laboratory and is located in the space of the Johnson Foundation. The instrument is on a 5x8 ft Newport optical table. The optical table also holds a programmable xenon flashlamp and a Spectra Physics DCR-11 pulsed laser and a PDL-3 dye laser. These allow for photo-activation of the sample within the IR instrument. This instrument is used primarily for static FTIR difference measurements. In addition, time-resolved FTIR kinetic experiments can be carried out using the laser system to trigger photochemical events. Researchers also have access to the RLBL where picosecond and femtosecond lasers are used to probe intrinsically fast chemical processes that occur in proteins and other macromolecular systems of biomedical interest. Time correlated single photon counting is used to study fast fluorescent events; transient absorption is used to investigate chemical processes which span over 13 orders of magnitude in time; near field optical microscopy can directly probe optical events on a 10 nanometer dimension. Other facilities at the University of Pennsylvania are also available for this project. The Chemistry Department houses the following facilities: Analytical NMR, Biological NMR, Chemistry Computer Facilities, Nucleic Acid Facility, Mass Spectroscopy and X-ray. The Department of Biochemistry and Biophysics in the Medical School houses an X-ray facility, a Computer facility and an Instrumentation Shop. This department also houses "The Molecular Simulation Laboratory" with Dr. Kim Sharp as director. The equipment includes the Silicon Graphics Power Challenge with 12 R10000 processors, 1 GB of RAM, 16 GB disk storage. Funds for this were obtained from NSF, the Department of Biochemistry and Biophysics and the Johnson Foundation. Other shared instruments of the Johnson Foundation include a CD spectrometer (AVIV 62DS), an ISS K2 Multi-frequency Phase Fluorimeter and a Bruker 300E EPR spectrometer. The proposed program seeks to extend the capabilities of the Bruker time-resolved FTIR spectrometer in several directions. In addition, the capability of carrying out three pulse echo experiments is also desired. Specifically the requested core equipment consists of 1) a Fourier transform Raman module; 2) optics for extension of FTIR capability into the visible and UV regions; 3) extension of the same instrument into the far-infrared to 20 cm-1; and 4) an ultra precision translation stage and controller to create a second optical delay line for three-pulse echo experiments.